The invention relates to a sensor arrangement and to a method for capturing a torque.
The invention comprises a sensor arrangement which functions according to the magnetic measuring principle and has the purpose of capturing a torque. Nowadays, magnetic measuring principles are frequently used in the field of torque and rotational angle sensors. In said sensors, a magnetic field which changes during a rotational movement is usually detected with Hall sensors. Furthermore, a resulting signal is converted into a rotational angle signal or torque signal.
Document DE 10 2005 031 086 A1 describes a sensor arrangement for capturing a differential angle. In this document it is proposed that magnetic field information of a magnetic circuit, which has a magnetic pole wheel and a ferromagnetic flux ring with teeth, is evaluated with at least one magnetic-field-sensitive sensor element. The teeth for radially tapping the magnetic field information of the magnetic pole wheel run in the radial direction.
In known sensor arrangements, the magnetic units and the carrier of magnetic-flux-conducting rings are mounted on two shafts which are connected to one another by means of a torque rod. The sensor unit is attached to a surrounding housing by means of a plug or a circumferential plug seal. As a result, the sensor arrangement is, however, mechanically overdetermined. Furthermore, a very large tolerance chain results between the surrounding housing with the mounted sensor unit and the carrier of magnetic-flux-conducting rings on the shaft, since a large air gap is present between the Hall circuits and the magnetic-flux-conducting rings which are composed of metal. This in turn requires a large magnetic field, for which reason significant reduction of the tolerance chain is aimed at.